The present invention relates to an electrostatic capacitance sensor.
Heretofore, as shown in Japanese Patent Laid-Open Publication No. 2010-127648 (hereinafter, referred to as Patent Literature 1), an electrostatic capacitance sensor has been known, in which an upper fixing plate and a lower fixing plate are joined respectively to front and back surfaces of a semiconductor substrate including a frame portion and movable bodies having movable electrodes.
In this Patent Literature 1, fixed electrodes arranged apart from the movable electrodes of the movable bodies so as to be opposite thereto are formed on the upper fixing plate. Moreover, central portions of the movable bodies are supported by beams, and gravitational center positions of both end sides of each of the movable bodies are made asymmetric to each other while taking, as a boundary, each of the central portions supported by the beams concerned, whereby the movable bodies swing in the event where an acceleration is inputted thereto.
Then, a difference of electrostatic capacitance to be changed between both end sides of each of the movable electrodes and the fixed electrodes in the event where the movable bodies swing is arithmetically operated, whereby a magnitude of the acceleration to be inputted is detected.